Spectroid

Carl Reinke

About this app

Spectroid is a real-time audio spectrum analyzer with reasonable frequency resolution across the the entire frequency spectrum.

💬 FAQ 💬

Q: Why are the dB values negative?
A: Spectroid uses dBFS (Full Scale) where 0 dB is the maximum power that the microphone can measure, so the decibel values are negative because the measured power is less than the maximum power.

Q: Can I zoom in on the spectrum plot?
A: Yes, do a two-finger pinch-to-zoom gesture.

Q: Why are there discontinuities/gaps in the spectrum plot and waterfall?
A: Spectroid uses multiple FFTs overlapped in frequency in order to provide better frequency resolution at lower frequencies than a single FFT. The caveat of this method is varied impulse response and minor discontinuities in frequency. The upside is that it can efficiently produce a spectrum that better matches the frequency resolution of human audio perception. It's still probably not as good as your ears though!

Q: Can I export the spectrum data?
A: Spectroid doesn't make your device a calibrated instrument. If you need the spectrum data then you should be using an actual spectrum analyzer rather than an app on your mobile device.

Ratings and reviews

I found these EVP sightings by accident. I did a screenshot on these figures that appeared in the graphs. I was a bit disturbed at a few readings but this app is on point with what it does the hardware is the only thing that I could think of that would be a variable depending on the device you are using. Great work I'd like to see a information tutorial for understanding the interface though.

Tested several free apps and this is the best hands down. Refresh is fast. Histogram feature is fantastic so you can see changes over time. Thank you for making this available. If I could request a feature it would be a filter function. I have a low frequency noise that is making it hard to see the singers vocals and would like to isolate them. Even without this is the best app.

Tried one or two others but then I found Spectroid. This is an amazing app. If you are an older sound engineer like me, you know there are feedback frequencies you can't even hear but younger audience members probably can. I can usually pick the frequency but sometimes you get dual-tone feedback that is harder to nail down. This app picks it up nicely. Some EQs light up the freq but I have 2 DBX 231s GEQs that do the job, as long as I can pick the frequency. Great app!!!

What's new

Fix missing spectrum plot on Android P.